Interim report large carnivore census Dinder NP, Sudan. Hans Bauer, Ameer Awad Mohammed, Mohammed Ahmed Ibrahim and Claudio Sillero-Zubiri

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1 Interim report large carnivore census Dinder NP, Sudan Hans Bauer, Ameer Awad Mohammed, Mohammed Ahmed Ibrahim and Claudio Sillero-Zubiri 20 February -13 March 2018, call-up survey Report published in Oxford, 12 April 2018 Wildlife Conservation Research Unit - University of Oxford (WildCRU); Sudan Wildlife Research Centre (SWRC); Sudan Wildlife Conservation General Administration (SWCGA). Funded by the Born Free Foundation and the Lion Recovery Fund. 1

2 Contents Summary... 3 Teams... 4 Introduction... 4 Area description... 4 Methods... 7 Results... 8 Discussion and recommendations Acknowledgements References Annex 1: Locations of the calling stations

3 Summary The objective of this mission was to survey populations of lion (Panthera leo) and spotted hyaena (Crocuta crocuta) in Dinder National Park (NP), Sudan, part of the Dinder-Alatash Transboundary Ecosystem. Lions are regularly observed inside both parks and in their immediate surroundings, but rarely, if ever, further than 10km outside the park. Hyaenas are rarely encountered and only at night but they are found in the entire landscape. We surveyed both species using call-ups or calling stations; counting individuals attracted to broadcasted sounds of prey species and hyaenas. We also tried to fit satellite collars to three lions. Our main conclusions are: 1. We estimate the lion population size at 157 (±26), and the spotted hyaena population at 180 (±18) individuals. These numbers are possibly too optimistic, since data from the core zone were extrapolated to inaccessible areas that are less well protected, including the entire southern half of Dinder NP. 2. These numbers are based on the assumption of average response rates found across Africa; if we add uncertainty about local parameters and take the extreme values of response rates minimum and maximum population size ranges are lions and hyaenas. The number of callups was also limited due to logistic constraints; our estimate must be considered as a working figure. 3. We only found lions in the core area of Dinder NP, the ~1000 km 2 area loosely defined here as a circle of 10km radius around main camp Gelego, which is obviously well protected and where prey densities are high. Outside the core area, prey densities are patchy but locally high, especially around permanent surface water. However, we never observed any lions in these outer areas (n.b. this is an area much larger than the official 5 km bufferzone along the perimeter), but we did observe livestock there on many occasions. A possible hypothesis is that livestock is compatible with prey species, but that lions are selectively killed by livestock attendants. Our survey included data from core and non-core areas of the park, but callups inside the core area are overrepresented compared to area size. Data are insufficient to calculate densities separately and we extrapolated the observed lion density to the entire park. 4. To ensure a robust and viable lion population, and to enable recolonization of Dinder NP by leopard from neighbouring Alatash NP, it is highly recommended to extend the area with a high level of protection beyond the core area and preferably to the entire park except the official bufferzone where mixed use is legally allowed. 5. From opportunistic sightings, we were able to add various species to the mammal list, and we reconfirmed the presence of the rare and near-endemic Heuglin s gazelle (Eudorca tilonura). Various observations reported here emphasise the importance of Dinder NP for Sudan savannah biodiversity conservation. 6. The collars were ordered on time and ready for delivery by the end of January. Due to low performance of the shipment company, however, the collars only arrived in Khartoum on 5 March. By that time, moonrise was so late that it was unlikely that we could immobilise any lions. We tried for 4 nights (6-10 March) and observed lions on multiple occasions, but never within shooting range and never with sufficient ambient light to enable darting. Further attempts will be made during a second visit. 3

4 Teams The first period team was composed of: 1. Hans Bauer (WildCRU) 2. Ameer Awad (SWRC) 3. Abdelraman Beigi (Ministry of livestock Resources, veterinary department) 4. Mohamed Ahmed (Police, Wildlife Conservation General Administration) 5. Shukrallah (Scout, Wildlife Conservation General Administration) 6. Aboutaleb (driver) Introduction The lion is a charismatic species and there is considerable international interest in its status. Recent publications have highlighted declines of lion range and numbers across Africa, especially in West, Central and East Africa (Bauer, 2015a). The lion is listed as Vulnerable on the IUCN Red List of Endangered Species (Bauer et al, 2015b), but the Red List contains no information on population status from Sudan. We therefore undertook the present survey to fill an existing knowledge gap of national and international significance. The mission reported here was undertaken with permission from the Sudan Wildlife Conservation General Administration (SWCGA). It was implemented in partnership by the Wildlife Conservation Research Unit, University of Oxford (WildCRU) and the Sudan Wildlife Research Center (SWRC) and the operational costs were partially covered by the Born Free Foundation (BFF) and the Lion recovery Fund (LRF). Area description Dinder NP (DNP) was created in 1935, but the boundaries were extended to include important wet season range so that the area is now 10,291km 2 (Fig. 1). DNP has a flat topography at an altitude of about 500 m asl. DNP has two seasonal rivers; the Dinder river and its tributary Gelego stream which have their confluence at Gelego Camp (DNP main station) and continue as Dinder, and the Rahad which is the northern boundary. These rivers are small in Ethiopia, but they gather more water from their basins and further downstream, especially in the West of the park, they have very large and wide permanent water ponds, locally called maya, and wildlife concentrates around these ponds. In addition to Dinder and Rahad rivers there are many small streams like khor Gelago, khor El Sunate and khor Masaweek. DNP is contiguous with the 2700 km 2 Alatash NP (ANP) in Ethiopia. Rainfall is highest in the south-easterly portion of the biosphere reserve ( mm), decreasing to mm in the North-East. The rainy season extends from May through November, with the peak in August. From November to February there is a cool dry period with daily maximum temperature averaging 30 C. From March to the onset of the rains, the weather is hot and dry with daily maximum temperatures averaging 38 C and a maximum of 44 C (Dasmann1972). 4

5 Figure 1: Map of Dinder-Alatash Trans Frontier Conservation Area, projected on Google earth (GERD = Great Ethiopian Renaissance Dam). Dasmann (1972) described two types of soils in Dinder biosphere reserve, the vertisols and entisols. The former, which are the most extensive in the park, are dark, heavy clay soils also known as black cotton soil with deep cracks during the dry season. The entisols dominate the eastern limits of the biosphere reserve towards the foothills of the Ethiopian plateau and along riverbanks. This type of soils occurs in patches of sandy loam and sandy clay. They intersperse with the vertisols. The main threat to the park is livestock encroachment, poaching and in the longer term possibly agricultural encroachment. Human presence in the park is evident and is said to be most worrisome in the southern parts, bordering the Gumuz areas, where charcoal making is severe. A special threat to lions is indiscriminate killing, especially by nomadic herdsman and prime among them are the Felata, who are pastoralists originally from West Africa but now with Sudanese nationality. They are armed with modern and traditional weapons and spend several months per year inside the park, with their livestock. DNP has one grader, five tractors, seven Land Cruiser trucks (many with cannons), 35 camels (used for patrols) and a few boats. There are 290 scouts in active service. The effective headquarters is Gelego; the camp has a GSM tower for the Zain cellphone network, has permanent solar and generator power, and has running water and a few buildings with beds ( hotel ). The park has several miradors and a dense road network in the core area with most maya s (waterholes), but also has remote zones with hardly any roads. At most of the important mayas, there is a camp for scouts with seasonal huts, a water pump, and in some cases additional infrastructure such as facilities for fishing. Mayas and their associated wildlife concentrations are thus guarded 24/7 throughout the dry season, and occasionally on camelback patrols in the wet season. Scouts are constantly rotated and spend at least half their time effectively patrolling the park. They official DNP Headquarters is in the 5

6 town of Dinder, with 90 staff, various infrastructures and a small zoo. It is 3 hours drive away from the park and is mostly concerned with administration. Sudan has a Ministry of Tourism, Heritage and Wildlife and a Ministry of Environment, but both ministries do not appear to have any presence on the ground. DNP is entirely managed by the SWCGA, which is a branch of the police and therefore falls under the Ministry of the Interior. Technically SWCGA falls under the supervision of ministry of Tourism, Heritage and Wildlife. Tora hartebeest (Alcelaphus buselaphus ssp. tora) were last observed in 1999, giraffe (Giraffa camelopardalis) were last observed in 1983 and elephants have not been seen for a long time. No particular reason was given for these extirpations, which may be partly due to climate and partly due to human influence. Presumably the leopard has recently been extirpated which would be due to the very intense poaching pressure on this particular species, linked to the strong culturally determined demand for leopard skin slippers throughout Sudan and the region. A census using camera traps failed last year in Alatash NP, mainly due to theft of cameras and the risk thereof; there is no reliable estimate of large carnivores in ANP (Ethiopia). The survey, however, did provide evidence of the presence of leopard (Panthera pardus) (Fig. 2). Leopards are probably fairly widespread at low densities throughout Ethiopia, and their presence in ANP is not very special for Ethiopia, but our photo is a significant observation for DNP in Sudan where the species is believed locally extinct. Figure 2: Leopard filmed by a camera trap in Alatash NP, Ethiopia DNP has developed in relative isolation for decades, perhaps not unexpected considering the wider political context of Sudan. As a consequence, conservation practice and conservation academia appear to be locally grounded but are not necessarily in synchrony with international best practice. A park like this in any other country in the Sudan-savanna belt would have attracted a lot of attention, participation and investment. DNP is currently a secret treasure with a much higher potential; it could be a major destination for tourism, research and international cooperation. 6

7 Methods We used the following methods: 1. Call-up (using 2x40 watt 100V amplifier and horn speaker system to play buffalo, pig and hyaena sounds; these sounds have a high probability to attract large carnivores within audible range). 2. Lion immobilisation and collaring equipment were available but not used. 3. Interviews with park staff. 4. Interviews with other stakeholders. Low carnivore densities and poor infrastructure in many areas across their range make surveying large carnivores expensive and time consuming. Therefore indirect methods are preferable (Midlane et al, 2015). Our study used call-ups, broadcasting recorded animal distress calls to attract lions and spotted hyenas (Ogutu and Dublin, 1998). Here we present the results of a call-up survey using the same methodology as Bauer (2007). Call-ups were done (cf. adapted according to Ogutu and Dublin,1998, Mills et al., 2001; Thorn et al., 2010) using the same protocol as Bauer (2007). We used a 2 x 40W amplifier and two speakers of 40W/100V to play hyena, buffalo and pig calls (courtesy of the African Lion Working Group) from a car (Toyota Hilux) roof. Each call-up was a cycle of three sessions of ten minutes of broadcast and ten minutes of silence, in which the recordings were alternated. After five minutes of broadcast, the speakers were turned 90 degrees to cover the area evenly with the call-ups. After each broadcast, the area around the car was scanned with a weak red light for eye reflections. The area was again scanned with a strong spotlight afterwards to assess the presence of lions or spotted hyenas. To minimize effects of weather, broadcasting time and habituation on response, we designed and executed the call-up surveys as followed: call-ups were played when carnivores were most active, from 7 pm to 12 pm. Secondly, we selected a random point on the main road, and thereafter spaced survey points 6 km apart on roads (straight-line distance; Figure 1). When visibility was limited by the vegetation, we relocated the call-up point a maximum of 500m in either direction. Each point was recorded with a GPS. No broadcasts were made with rain or high wind velocities, although wind speed and luminosity were not specifically recorded. Many animals which were attracted by the call-ups were skittish, so approaching lions and hyenas were mainly counted based on their vocalisations and eye reflections. When animals were close, individuals could be observed, followed with a torch and counted. The spotlight was also used to check for possibly undetected hyenas and lions after each call-up (Bauer, 2007). To minimise double counting the same individual, calls that originated from the same location and could not be differentiated clearly, were counted as one individual. The eye reflections counts were only a minimum count and more individuals could have been around the car. Due to logistic and ecological constraints, local calibration of the call-ups was not possible. In order for the call-up surveys to be compatible for comparison, we followed Bauer s (2007) assumptions; both species had an effective range of 3 km and response rate of 75%, to give a mean (±SD) density per call-up. This calibration was selected, because (1) the survey took place in the same habitat type, (2) in the same period of the dry season, (3) the same buffalo calf distress and hyena call audio track were used and (4) there were non-baited call-ups. Since large carnivore densities in our survey areas 7

8 are low, double counting is unlikely (Kirsten et al., 2016). Furthermore, we generated a plausible range of the population size using the extreme values for the response rate (50-100%) found in the literature (Ogutu and Dublin, 1998; Mills et al., 2001; Ferreira and Funston, 2010; Cozzi et al., 2013; Ferreira and Funston, 2016). Results The diversity and abundance of wildlife in DNP is impressive, and for an outsider also surprising since DNP is not much advertised and hardly known in internationally accessible scientific literature. Our opportunistic sightings and observations are listed in Table 1; it is possibly not exhaustive and more species are likely to be found in future. There is an urgent need for a critical review of surveys in the past, for a camera trapping study and for a properly designed survey using standard distance transects on foot. We performed 21 callups (see annex 1), during which we had responses of 8 hyaenas (Standard Deviation 0.80) and 7 lions (Standard Deviation 1.54). Hyaenas mostly approached the car and were visible in the dark, but running away from light; in contrast, no lion approached the car in response to any of our callups and all responses were roars. Assuming an effective range of 3 km, our callups covered an area of 21*π*3 2 =594 km 2 ; extrapolation to the size of DNP gives a population size of 157 (±26) lions and 180 (±18) spotted hyaenas. These numbers are based on the assumption of average response rates found across Africa (0.75); if we add uncertainty about local parameters and take the extreme values of response rates (0.5-1) then our minimum and maximum population ranges are lions and hyaenas. Lion numbers were sensitive to an exceptional response of 5 lions at the main camp, Gelego; if this observation is treated as an outlier and removed from the dataset the lion estimate drops to 47 (±27) with a range of On the other hand, the fact that no lions approached the car demonstrate that response rate was probably low with lions being skittish due to persecution and/or limited exposure to cars due to the absence of tourists; this suggests that we may have underestimated population size. We only found lions in the core area of Dinder NP, the ~1000 km 2 area loosely defined here as a circle of 10km radius around main camp Gelego plus a western extension along the Dinder river, which is obviously well protected and where prey densities are high(fig. 2). Outside the core area, prey densities are patchy but locally high, especially around permanent surface water. However, we never observed any lions in these outer areas (n.b. this is an area much larger than the official 5 km bufferzone along the perimeter), but we did observe livestock there on many occasions. A possible hypothesis is that livestock is compatible with prey species, but that lions are selectively killed by livestock attendants. Our survey included data from core and non-core areas of the park, but callups inside the core area are overrepresented compared to area size (Fig. 3). Data are insufficient to calculate densities separately and we extrapolated the observed lion density to the entire park. The result may be an optimistic figure under present conditions. To ensure a robust and viable lion population, and to enable recolonization of Dinder NP by leopard from neighbouring Alatash NP, it is highly recommended to extend the area with a high level of protection beyond the core area and preferably to the entire park except, maybe, the official bufferzone where mixed use is legally allowed. 8

9 Table 1: List of mammal species of Dinder NP, updated from Awad (2014); last column indicates information obtained on our 2017 and 2018 trips. English name Scientific name Source / remarks Carnivores Carnivora Lion Panthera leo Observed Civet Civettictis civetta Mohammed (2014) African (golden) wolf Canis anthus Mohammed (2014) and/or golden jackal* (Canis lupaster) Striped hyaena Hyaena hyaena Mohammed (2014) Spotted hyaena Crocuta crocuta Observed Egyptian mongoose Herpestes ichneumon Observed Wild cat Felis sylvestris Observed Honey badger Mellivora capensis Observed Genet Genetta genetta Observed Rodents Rodentia Crested Porcupine Hystrix cristata Observed Ungulates, even-toed Artiodactyla Warthog Phocochoerus africanus Observed Buffalo Syncerus caffer Observed Bushbuck Tragelaphus scriptus Observed Waterbuck Kobus ellipsiprymnus Observed Roan antelope Hippotragus equinus Observed once Greater kudu Tragelaphus strepsiceros Mohammed (2014) Heuglin s gazelle 1 Eudorca tilonura Observed Reedbuck Redunca redunca Observed Oribi Ourebia ourebia Observed Kob 2 Kobus kob Observed Primates Primates Olive baboon Papio anubis Observed Moustached monkey 3 Erythrocebus poliophaeus Observed Vervet Cercopithecus aethiops Observed Bushbaby, presumably Senegal galago Galago sp. (senegalensi?) Observed 1: Hitherto often incorrectly listed variously as red fronted or Thomson s gazelle (Eudorcas rufifrons / Eudorcas thomsoni), the gazelle species found in DNP is Heuglin s gazelle which is of tremendous conservation importance since this may be the last remaining population of the species. 2: There are several kobs among the groups of reedbuck, these may have gone unnoticed but we are confident that we identified them correctly. This means a range expansion for the species of >400 km north and east, also the first record East of the river Nile. 3: Hitherto listed as patas (Erythrocebus patas), but recent morphological evidence described the population East of the river Nile as a separate species (Gipolitti 2017); Dinder would be the most effectively protected population in its range and therefore the core conservation area for the species. 9

10 Figure 2: Core area of Dinder NP Figure 3: Map of Dinder ecosystem 10

11 Discussion and recommendations With 157 (±26) lions and 180 (±18) spotted hyaenas, populations DNP are potentially viable; they are below the threshold of 500 which is considered safe, but they are above the critical threshold of 50 individuals. Viability of the lions and other species in DNP is boosted by connectivity with ANP where the population appears to be small, but which is important as a source for possible recolonization of the leopard. There is some uncertainty inherent to our methods, but the ranges of values that we calculated when various parameters are considered do not substantially alter this finding. There are ~100 populations with a total of ~ lions in Africa (Bauer et al., in prep.); on the scale of the continent the DNP lions are not game changers for species survival. However, at the national level it is probably the only population that is effectively protected and that is expected to be secure for future generations of the people of Sudan. It is almost certain that the lions in Sudan belong to the sub-species Panthera leo leo found across India and West, Central, North Africa. This sub-species has declined precipitously over the last two decades and only ~10 populations remain, with an estimated ~1500 lions. The lion population of DNP is therefore one of the more robust populations and is of regional conservation interest. Recommendations: 1. Continue current good management practices with a strong emphasis on law enforcement; management currently practised in the core area should be extended to the entire park, except the bufferzone where mixed use is allowed. 2. Carry out wildlife census (aerial survey, foot transects); 3. Set up a permanent camera trapping grid to survey and monitor wildlife; 4. Promote greater awareness for this area, within Sudan and internationally, starting with a good website including professional pictures and video clips. 5. Gradually improve tourism development, community development, fire management, ecological monitoring, introduction of SMART and other technologies; 6. Perform an institutional review of park management by the police and the potential role of other stakeholders to support further park development; 7. While the wildlife sector in Sudan has a long tradition, it has also been in isolation for a long time; overall capacity development of all stakeholders is highly recommended. 8. Promote further cooperation with Ethiopia, aiming at harmonisation of management, particularly in terms of infrastructure development, law enforcement and ecological monitoring of DNP and ANP; 9. Seek joint dialogue with stakeholders, especially Felata communities; 10. Actively seek international financial support for this important area. 11

12 Acknowledgements The Born Free Foundation and Lion Recovery Fund kindly funded the operational cost of this mission. In Sudan, a vehicle was provided by the SWRC, for full support and information we are grateful to Dr. Khalid and Prof. Aisha Elfaki of SWRC. We also thank SWCGA, especially the Director General Maj.Gen. Jemal Aldin elballa, vice Director Maj.Gen. Adam Hassan, Protected Area Director Maj. Gen Kahal. Director of international cooperation at WCGA Maj.Gen Suliman Ali Hakim and the Director of Dinder NP Maj. Gen Jemal Elbid. We thank the staff of DNP in Gelego camp and other camp inside DNP, in particular Mr. Jemal, Mr. Ibrahim and Mr. Hatim. We also thank Dr. Taha, Reem and Karlos for sharing the camp. Our thanks also extend to the General Directorate of Epidemiology - ministry of animal resources for providing us the Dartgun, and in particular to Dr. Abdel Rahman Beigi who joined us to the field. References Bauer, H. (2007). Status of large carnivores in Bouba Ndjida National Park, Cameroon. African Journal of Ecology, 45, Bauer, H.& Gebeyehu Rskay (2016) Reconnaissance visit to Alatash Dinder Lion Conservation Unit, Ethiopia Sudan border. WildCRU, University of Oxford. Bauer, H.,G. Chapron, K. Nowell, P. Henschel, P. Funston, L. Hunter, D. Macdonald, C. Packer (2015a) Lion (Panthera leo) populations are declining rapidly across Africa, except in intensively managed areas. PNAS 112 (48) Bauer, H., Packer, C., Funston, P.F., Henschel, P. & Nowell, K. (2015b) Panthera leo. The IUCN Red List of Threatened Species 2015: e.t15951a Downloaded on 01 December Cozzi, G., Broekhuis, F., Mcnutt, J. W., & Schmid, B. (2013). Density and habitat use of lions and spotted hyaenas in northern Botswana and the influence of survey and ecological variables on call-in survey estimation. Biodiversity and conservation, 22, Dasmann, W.P. (1972). Development and Management of the Dinder National Park and its wildlife. FAO No. TA Rome. pp.61. Ferreira, S. M., & Funston, P. J. (2010). Estimating lion population variables: prey and disease effects in Kruger National Park, South Africa. Wildlife Research, 37, Ferreira, S. M., & Funston, P. J. (2016). Population estimates of spotted hyaenas in the Kruger National Park, South Africa. South African Journal of Wildlife Research, 46, Gippoliti, S. (2017) On the Taxonomy of Erythrocebus with a Re-evaluation of Erythrocebus poliophaeus (Reichenbach, 1862) from the Blue Nile Region of Sudan and Ethiopia. Primate Conservation, 31,

13 Kirsten, I, Bakker, CE, Trujilo, LL, Bour, P., Bauer, H. & De Iongh, H.H. (2017). Lion (Panthera leo) and Spotted Hyena (Crocuta crocuta) abundance in Bouba Ndjida National Park, Cameroon; trends between 2005 and Afr J Ecol. 2017;00:1 4. Koepfli K.-P., Pollinger J., Godinho R. et al.(2015) Genome-wide Evidence Reveals that African and Eurasian Golden Jackals Are Distinct Species. Current Biology 25, Midlane, N., O riain, M.J., Balme, G.A. & Hunter, L.T. (2015). To track or to call: comparing methods for estimating population abundance of African lions Panthera leo in Kafue National Park. Biodiversity and Conservation, 24, 1-17 Mills, M.G.L., Juritz, J.M. & Zuccini, W. (2001). Estimating the size of spotted hyaena (Crocuta crocuta) populations through playback recordings allowing for nonresponse. Animal. Conservation, 4, Mohammed, A.A. (2014) Changes in Vegetation Cover and Impacts of Human Population in Dinder National Park, Sudan During the Period from 1972 to PhD Thesis, Sudan Academy of Sciences, Khartoum. Ogutu, J.O., & Dublin, H.T., (1998). The response of lions and spotted hyaenas to sound playbacks as a technique for estimating population size. African Journal of Ecology, 36,

14 Annex 1: Locations of the calling stations 14